1 files changed, 63 insertions, 0 deletions
diff --git a/webrtc/modules/video_coding/timestamp_map.cc b/webrtc/modules/video_coding/timestamp_map.cc
new file mode 100644
index 0000000000..97d2777658
--- /dev/null
+++ b/webrtc/modules/video_coding/timestamp_map.cc
@@ -0,0 +1,63 @@
+/*
+ *  Copyright (c) 2011 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#include <assert.h>
+#include <stdlib.h>
+
+#include "webrtc/modules/include/module_common_types.h"
+#include "webrtc/modules/video_coding/timestamp_map.h"
+
+namespace webrtc {
+
+VCMTimestampMap::VCMTimestampMap(size_t capacity)
+    : ring_buffer_(new TimestampDataTuple[capacity]),
+      capacity_(capacity),
+      next_add_idx_(0),
+      next_pop_idx_(0) {}
+
+VCMTimestampMap::~VCMTimestampMap() {}
+
+void VCMTimestampMap::Add(uint32_t timestamp, VCMFrameInformation* data) {
+  ring_buffer_[next_add_idx_].timestamp = timestamp;
+  ring_buffer_[next_add_idx_].data = data;
+  next_add_idx_ = (next_add_idx_ + 1) % capacity_;
+
+  if (next_add_idx_ == next_pop_idx_) {
+    // Circular list full; forget oldest entry.
+    next_pop_idx_ = (next_pop_idx_ + 1) % capacity_;
+  }
+}
+
+VCMFrameInformation* VCMTimestampMap::Pop(uint32_t timestamp) {
+  while (!IsEmpty()) {
+    if (ring_buffer_[next_pop_idx_].timestamp == timestamp) {
+      // Found start time for this timestamp.
+      VCMFrameInformation* data = ring_buffer_[next_pop_idx_].data;
+      ring_buffer_[next_pop_idx_].data = nullptr;
+      next_pop_idx_ = (next_pop_idx_ + 1) % capacity_;
+      return data;
+    } else if (IsNewerTimestamp(ring_buffer_[next_pop_idx_].timestamp,
+                                timestamp)) {
+      // The timestamp we are looking for is not in the list.
+      return nullptr;
+    }
+
+    // Not in this position, check next (and forget this position).
+    next_pop_idx_ = (next_pop_idx_ + 1) % capacity_;
+  }
+
+  // Could not find matching timestamp in list.
+  return nullptr;
+}
+
+bool VCMTimestampMap::IsEmpty() const {
+  return (next_add_idx_ == next_pop_idx_);
+}
+}  // namespace webrtc